Qt 5.15.1 is a bug-fix release. It maintains both forward and backward
compatibility (source and binary) with Qt 5.15.0.

For more details, refer to the online documentation included in this
distribution. The documentation is also available online:

  https://doc.qt.io/qt-5.15/index.html

The Qt version 5.15 series is binary compatible with the 5.14.x series.
Applications compiled for 5.14 will continue to run with 5.15.

Some of the changes listed in this file include issue tracking numbers
corresponding to tasks in the Qt Bug Tracker:

  https://bugreports.qt.io/

Each of these identifiers can be entered in the bug tracker to obtain more
information about a particular change.

****************************************************************************
*                                  QtQml                                   *
****************************************************************************
 - [QTBUG-83384] Fixed various failing assertions in the JIT compiler.
 - [QTBUG-85605] QQmlObjectCreator: fixed member func call with this == nullptr
 - [QTBUG-84104] Fixed a regression in QMetaType::registerConverter()
   with converting JS arrays to sequence<T> types.
 - [QTBUG-84447] Invokable methods of Q_GADGET objects are now fully accessible.
 - [QTBUG-84095] Fixed an invalid memory read in QQmlContextData::emitDestruction()
 - [QTBUG-84692] Fixed a race condition in QQmlData::createPropertyCache
 - [QTBUG-84237] Fixed a bug which prevented inline components from accessing
   inner objects in some cases.
 - [QTBUG-83121] QQmlEngine::baseUrl() no longer returns an empty url
   if the current path is the root directory.
 - [QTBUG-83214] Fixed a memory leak in a StateMachine with signal handler.
 - [QTBUG-84474] On all platforms other than Windows, QTimeZone::systemTimeZone()
   is now used when converting from times such as QTime(0, 0, 0), to avoid
   incorrect daylight-saving accounting in the BST timezone.
 - [QTBUG-83352] Fixed a crash caused by QQmlDelegateModel items being
   deleted while being removed from the cache.
 - [QTBUG-83354] We now warn about circular dependencies between QML types while loading.

 - qmlformat tool:
   * [QTBUG-85321] Fixed handling of empty blocks.
   * [QTBUG-85035] Nested functions no longer get moved to the top level.
   * [QTBUG-85077] Braces are no longer removed from nested if's.
   * [QTBUG-85003] Fixed the trailing newline in if blocks so that the
     formatting is stable during repeated runs.
   * [QTBUG-85189] Inline components are now formatted correctly.
   * [QTBUG-85289] Bindings that take up multiple lines are now formatted correctly.
   * [QTBUG-84599] String literals are not reformatted: thus unicode
     escape sequences are now preserved.

 - Qt Quick Compiler:
   * [QTBUG-85243] Revived QTQUICK_COMPILER_SKIPPED_RESOURCES for cases when
     some resources should not be compiled with qmlcachegen.
   * [QTBUG-84901] Fixed compilation from a different drive on Windows
     by converting the colon after the drive letter to an underscore.

****************************************************************************
*                                 QtQuick                                  *
****************************************************************************

 - Accessibility:
   * [QTBUG-83738] Fixed a crash when the Accessible attached property was
     accessed on ApplicationWindow or another non-Item object.
   * [QTBUG-82433] Screen readers (such as Windows Narrator) no longer
     spell out the characters in TextInput { echoMode: TextInput.Password }

 - AnimatedSprite:
   * [QTBUG-63942] AnimatedSprite now resumes playback when it becomes
     visible again, if it was playing when it was hidden.

 - Event Handlers:
   * [QTBUG-85303] In a HoverHandler with a margin and a cursorShape, the
     cursor now changes within the margin area.

 - Flickable:
   * [QTBUG-31905] With AutoFlickDirection and AutoFlickIfNeeded,
     we now take margins into account to avoid unnecessary scrolling.

 - Item:
   * [QTBUG-55879] grabToImage() now works with QQuickRenderControl.
   * [QTBUG-40220] If polish() is called within updatePolish(), or a polish
     loop occurs for some other reason, the detection is now more correct, and
     the warning occurs after 1000 such loops.  The loop is broken after
     100,000 times, to avoid the application becoming unresponsive.

 - Item views:
   * [QTBUG-82989] Since the parent of a delegate can end up being null during
     its lifetime, developers are now advised against using it in bindings.
   * [QTBUG-83956] TableView now allows negative spacing, which is useful
     to cause delegates with borders to overlap and make a single-pixel grid.
   * [QTBUG-84046] During layout, TableView now sets item width before height.
     This works better with text items like TextEdit which calculate implicit
     height based on the assigned width, (because of word-wrap.
   * [QTBUG-84604] Fixed a culling regression when using ListView with ObjectModel.

 - Layouts:
   * [QTBUG-71839] Performance improvements to Qt Quick Layouts. This has the
     small side-effect that size hint (implicitWidth/implicithHeight etc)
     changes are not immediately emitted after a layout has been modified.

 - MouseArea:
   * [QTBUG-82382] Dragging can no longer be started with non-accepted mouse buttons.
   * [QTBUG-85111] Fixed a regression in mouseX/mouseY calculations during
     dragging of a MouseArea whose position is not 0,0.

 - Rectangle:
   * [QTBUG-84069] Named preset gradients are working again.

 - Repeater:
   * [QTBUG-83356] keyboard.left/keyboard.right navigation now works when
     setting up navigation to Repeater-created siblings.

 - RHI / scene graph:
   * [QTBUG-85965] If the first node in a batch becomes invisible due to opacity
     change, it now triggers rebuilding the batch.
   * [QTBUG-85996] Fixed a crash in QSGBatchRenderer::Renderer::updateStencilClip()
     due to clipNext being null.
   * [QTBUG-65170] Fixed a crash when QSGTexture is deleted in rc->endSync()
   * [QTBUG-83319] Fixed a crash in QQuickWidget when failing to make the OpenGL
     context current in createFramebufferObject() during resizing.

 - Shapes:
   * [QTBUG-82371] Fixed a crash on eglfs.

 - Window:
   * Pass input method events on to the focus item.
   * [QTBUG-82815] A transient Window declared in an Item which is shown via
     QQuickWidget now becomes visible even though the parent window is offscreen.

 - Text:
   * [QTBUG-69301] Fixed Outline style on connected glyphs, especially visible
     in e.g. Arabic and Indic writing systems.
   * [QTBUG-85514] Fixed a regression in antialiasing on outlined text.
   * [QTBUG-81810] Fixed a bug where we would sometimes resolve the wrong fonts
     inside .ttc font collections.
   * [QTBUG-49646][QTBUG-84021] Fixed kerning with horizontalAlignment: center.
   * [QTBUG-84454] Fixed an offset on text position when combining
     NativeRendering with high-dpi scaling.
   * [QTBUG-80180] Fixed a clipping bug in software-rendered text.
   * [QTBUG-83819] If the selection color is transparent, it is not
     rendered, to avoid problems with blending.
   * [QTBUG-84981] Fixed the vertical alignment of images in a text document
     to align with the HTML standard as much as possible: AlignMiddle
     is between AlignTop and AlignBottom.
   * [QTBUG-84351] Optimized text glyph geometry updating by doing it
     only when necesssary rather than in scene graph preprocessing.

****************************************************************************
*                      Platform Specific Changes                           *
****************************************************************************

 - [QTBUG-84497] Fixed build issue on Windows when using nmake
   (RegExpJitTables.h was not generated correctly).
 - [QTBUG-83115] On webOS, Images with the same source are now shared even if
   the cache property is false.
 - [QTBUG-83119] On webOS, synthetic hover events are no longer sent on
   frame update.